Measuring and controlling system



Get. 20, 1195 9 F ALEXANDER 2,909,660

MEASURING AND CONTROLLING SYSTEM Filed Nov. 26, 1957 United States Patent 2,909,660 MEASURING AND CONTROLLING SYSTEM Frank M. Alexander, Columbus, Ohio, assignor to Industrial Nucleonics Corporation, a corporation of Ohio November 26, 1957, Serial No. 698,952

Application 6 Claims. (Cl. 250-52) having a plurality of local profile adjustments.

The invention will be illustrated and described in connection with a paper making machine of the Fourdr-inier type, although it will be understood that such illustration and description are merely exemplary in that the principles and the means provided by the invention may be as well adopted with little or no modification to other industrial processes wherein similar control problems are existent.

In Fourdriniermachines, the paper stock is discharged from the head box onto the forming wire through an ad justable opening which controls the rate of flow and amount of the stock being deposited on the wire. This opening is commonly defined by the head box apron, side walls and an adjustable slice or slice assembly which can be moved towards or away from the apron to regulate the size of the opening. Since the flow of stock may vary both in density and in rate of flow across the discharge opening, the slice is frequently provided with some kind of a flexible slice plate or lip having a plurality of local contour adjustments over the length thereof to compensate for variations that would otherwise occur in the rate of pulp delivery across the width of the forming wire. The desired uniformity of the sheet profile may also be affected adversely by variations in the moisture removal operations along the Fourdrinier wire section. At the present time any obvious irregularities in the profile thickness can be corrected only by a rather unsatisfactory 7 manual slice adjustment procedure, in which the paper machine operator is required to mount the stock head box and manipulate one or a plurality of hand wheels or similaradjustors. Such a procedure requires the absence of the operator from his normal controlling station, and involves considerable time lags between the observation of an irregularity, a corrective adjustment to the slice, and the determination of the effect thereof. The amount of correction is determined only by the skill of the particular operator and varies from one operator to another. Furthermore, there is presently available no means for providing the operator accurate and complete information whereby he may quickly determine the immediate relationship between a particular combination of slice settings and the profile formation of the web produced thereby. Were such indication available, trends toward profile malformation could be predicted and anticipatorily compensated for by appropriate changes in the settings of the slice.

In accordance with this invention, there is provided a conveniently located control and readout panel whereon graphical displays of accurate profile measurements are rapidly and automatically plotted and recorded in repeating sequence. These measurements are obtained from a gauging instrument which cyclically scans the entire width of the web, generating a continuous electrical analog of the physical property of interest, such as weight per unit area or thickness of the sheet at the instantaneous point of measurement. The control panel display further provides a remote indication of the position of each individual slice adjustment. Also mounted on the panel are remote controls whereby the operator may positively reposition each local slice adjustment, guided by the appearance of the graphical profile plot and the slice position indications presented on the panel before him.

It is the primary object of the present invention to provide a paper making machine of the Fourdrinier type having means for remotely controlling the flow of paper stock from the head box to the forming Wire thereby enabling the production of high grade paper with a truly uniform widthwise profile.

A further object of the invention is to provide improved stock flow control means for paper making machinery which can be applied to present machine installations of conventional design and is practical and efiicient to operate.

It is another object of this invention to provide a means for indicating at some convenient manual control point, the amount of slice opening at predetermined points along the slice of a Fourdrinier paper making machine.

It is still another object of this invention to provide with a paper making machine, a means for combining a slice position indicator, a paper stock basis Weight or profile indicator, and a means for remote adjustment of said slice, thereby enabling the machine operator to elfect more rapid control of widthwise paper stock profiles, and a more facile and rapid judgment of necessary slice corrections needed.

Other objects and advantages will become apparent from the following description read in conjunction with the accompanying drawings wherein:

Fig. l is a diagrammatic representation of this invention and the typical apparatus with which it is operative, and

Fig. 2 is a schematic of the circuitry for operating a slice position indicator.

Referring to Fig. 1, there is shown a general scheme of the Wet section of the Fourdrinier paper making process. A sheet of paper stock is shown in the process of formation by machinery including a head box 102 wherefrom a laterally extended flow of paper stock is discharged through an adjustable slice 104. Stock input to the head box is indicated generally at 106. The paper stock passes onto a wire 108 and then over the breast roll 110 after which moisture is removed from the distributed paper stock through both capillary and gravitational action by means not shown. The mat leaves the wire 108 at the couch roll 116 and passes through the presses 118 and 120. Immediately following the presses, the sheet 100 is shown to pass through a non-contacting thickness gauge at 130. Further description of the paper making process is not included, as it will not be an influencing factor on the control invention herein disclosed.

A thickness gauge comprises a U-bracket 131 supporting a source of radiation in a lower housing (shown only in dotted line at 133b) located directly under an upper head 132 and below the sheet 100. The lower housing is attached to the lower arm of the U-bracket 131 so that it remains directly under the upper housing 132. A radiation detector such as an ion chamber is located in the upper housing 132 to accept pentrative radiation passing upward through the sheet 100 thereby generating a thicknessfunctional voltage which is transmitted over line to measuring circuits located at 136. The gauge 13-0 traverses the width of the sheet 100 on a rail 129 by means of a traversing motor 134 actuated by a scanning control circuit shown at 133. Sheet 100 is divided width-wise by dotted lines into six equal areas reprethe sheet 100. Directions are denoted as seen by an ob-- server facing the slice-lip opening of the head box 102.

Only when the gauging head 132 is positioned at the right-hand edge of the sheet 100, will the scanning control actuate the traversing motor 134 to slowly move the gauge 130 to the left. The gauge will sequentially scan areas a, b, c, d, e, and f in its continuous movement over the sheet. Upon completion of the scanning of area f, the motor 134 is reversed by the scanning control 138 so that the gauge is rapidly re-positioned over the righthand edge of the sheet 100. As soon as this position is attained, the gauge will brake and initiate another scanning sequence over areas a through 1.

A voltage signal representing paper stock thickness at the traversing point of measurement is produced by the gauge 130 and transmitting over line 135 to the gauge circuitry shown generally at 136. Circuit 136 is fully described in a US. patent, No. 2,790,945, issued April 30, 1957, to H. R. Chope.

As the gauge traverses and continuously measures the sheet 100 from the profile area a through 1, servo motor 21 positions the recorder chart drum 24 through mechanical linkage 22 in accordance with basis weight signal variations. Simultaneously the recorder pen 26 is moved across the chart 28 by a suitable connection 146 with the gauge traversing motor 134 so as to correlate the pen position with the gauge measuring position on the sheet v100.

Referring to head box 102 and its associated apparatus, the slice motors 71 through 76 are coupled to gearing devices 71g through 76g for the purpose of reducing the speed of the slice motors to a practical value needed for quick and precise screw-down of the separate portions of the flexible slice lip 104. Each of these slice sectionsstarting from the right-hand side of the sheet controls an area of the sheet 100 previously referred to as areas a through 1. Slice motor 71 controls the vertical position of the slice lip over area a, slice motor 72 controls the slice over area b, and so on.

Each of the motors 71 to 76 is energized by a switching means 50a-50f on console unit 200 as typically shown in the preferred embodiment of the present invention. Each of the three position switches operates its corresponding motor in either a clockwise or counterclockwise direction through the gear box, to move one of the slice control shafts up or down. All slice motor control switching is shown as centralized at console 200 together with the recorder chart for ease of operation. Control between the slice motors 71 through 76 and the switching mechanism 50a-50f on the console 200 is shown generally by lines 5211-521.

There is associated with each of the switches 50a-50f on the console 200, a group of bar volt meters 1 to 6 to indicate slice position. Referring now to Fig. 2 the circuitry of these meters is shown in detail. The overall bridge circuit is energized by a battery 80 on an exterior arm thereof and resistances .103 and 107 provide a voltage division at 105 for the inter-arm coupling line 106. Voltage over the whole bridge is adjusted by the potentiometer 82. Each of the inner arms of the bridge contains a potentiometer as at 84, 90 and 96 which, in turn, are controlled by mechanical linkages 10, 2c or 3c. These linkages are in turn actuated by a corresponding slice motor at 71 through 76.

The variable contacts of potentiometers 84, 90 and 96 are each directed into bar voltmeters 1, 2 and 3. In operation of this circuit when the slice adjusting motor 72 is energized, mechanical linkage 2c will change the setting of potentiometer 90 and thereby change the reading on bar voltmeter 2. This change in reading is caliat the'particular point of slice control, in this case, control point 2. Bar voltmeters 1, 2 and 3 are calibrated :brated to correspond with the amount of slice movement by adjusting potentiometers 86, 92 and 98 respectively. The bridge contains as many inner arms as there are slice control points, although only three of these arms are shown in Fig. 2 in the interest of simplicity, and the break at 112 is indicative of any preferred circuit continuity.

The potentiometers 84, and 96 in a constructed embodiment would be incorporated in gear boxes 71g through 76g of Fig. 1 with appropriate return wires to the bar voltmeters on the console unit 200 (not shown). The dials on bar voltmeters 1 through 6 of Fig. l are calibrated to read in convenient units of measurement, i.e., thousandths of an inch, and are so arranged on console 200 to apprise the paper machine operator with slice position information of the actual profile of the mat-forming slice. Two important and interrelated facets of control information are, therefore, available at the console 200. With its use, the operator at a convenient control station can readily observe the lateral cross section of the mat produced on the wire and the profile of the slice producing said mat.

With the above relationship immediately available, rapid judgment of any necessity for slice adjustment can be effected, and immediate correction can be made by operating the convenient actuating switches at 50a-50f.

Although certain and specific embodiments may have been shown, it is to be appreciated that modifications may be had without departing from the true spirit of the invention.

What is claimed is:

l. The combination, with a manufacturing machine for continuously producing a laterally extended length of a formed product, of flow regulating means for fornnng a cross-sectional dimension profile of said product across the width thereof, said flow regulating means including a row of local profile adjustments each affecting said dimension at a portion of said width, said portion being substantially less than the total extent of said width; means for gauging said dimension, means for mounting said gauging'means on the product output side of said machine, traversing means associated with said mounting means for causing said gauging means ,to cyclically scan said product to and fro across said width thereof, means connected to said gauging means for generating a first signal indicative of said dimension at the traversing point of measurement, means interconnected with said traversing means for generating a second signal indicative of the instantaneous scanning location of said gauging means relative to said product, recorder means receiving said first and second signals for indicating the function thereof in two coordinates so as to graphically-display said dimension profile, means for actuating each of said local profile adjustments, and means for controlling each of said actuating means independently.

2. The combination of claim 1 wherein said gauging means comprises a source of penetrative radiation and a radiation detector, means supporting said source to provide a beam of radiation directed across the path of said product and for supporting said detector in position to receive radiation from said product, and wherein the value of said first signal is dependent on the output of said detector.

3. The combination of claim 1 wherein said recorder means includes a display chart subdivided to correspond to local sections of said profile in turn corresponding to laterally extended local areas of said product, means controlled by variations in one of said first and second signals for driving said chart, an indicator movable with respect to said chart, and means controlled by the other of said first and second signals for driving said indicator.

4. The combination, with a manufacturing machine for continuously producing a laterally extended length of a formed product, of flow regulating means for forming a cross-sectional dimension profile of said product across the width thereof, said flow regulating means including a row of local profile adjustments each affecting said dimension at a portion of said width, said portion being substantially less than the total extent of said width; means for gauging said dimension,means for mounting said gauging means on the product output side of said machine, traversing means associated with said mounting means for causing said gauging means to cyclically scan said product to and fro across said Width thereof, means connected to said gauging means for generating a first signal indicative of said dimension at the traversing point of measurement, means interconnected with said traversing means for generating a second signal indicative of the instantaneous scanning location of said gauging means relative to said product, an operators station, recorder means located at said operators station and receiving said first and second signals for indicating the function thereof in two coordinates so as to graphically display said dimension profile, means for actuating each of said local profile adjustments, and means at said operators station for manually controlling each of said actuating means independently.

5. The combination, with a manufacturing machine for continuously producing a laterally extended length of a formed product, of flow regulating means for forming a cross-sectional dimension profile of said product across the Width thereof, said flow regulating means including a row of local profile adjustments each affecting said dimension at a portion of said width, said portion being substantially less than the total extent of said width; at source of penetrative radiation and a radiation detector located on the product output side of said machine, means supporting said source to provide a beam of radiation directed across the path of said product and for supporting said detector in position to receive radiation from said product, a track extending laterally across the width of said product, a carriage bearing said source and detector supporting means on said track, motor means for actuating movement of said carriage on said track, a program controlled switching device to periodically start, stop and reverse said motor so as to continuously reciprocate said carriage on said track, circuit means including said detector for generating a first signal indicative of said dimension at the traversing point of measurement, means interconnected with said motor and carriage for generating a second signal indicative of the instantaneous scanning location of said source and detector relative to said product, an operators station, recorder 6 means located at said operators station and receiving said first and second signals for indicating the function thereof in two coordinates so as to graphically display said dimension profile, means for actuating each of said local profile adjustments, and means at said operators station for manually controlling each of said last-named actuating means remotely and independently.

6. The combination, with a manufacturing machine for continuously producing a laterally extended length of a formed product, of flow regulating means for forming a cross-sectional dimension profile of said product across the width thereof, said flow regulating means including a row of local profile adjustments each affecting said dimension at a portion of said width, said portion being substantially less than the total extent of said width; means for gauging said dimension, means for mounting said gauging means on the product output side of said machine, traversing means causing said gauging means to cyclically scan said product to and fro across said width thereof, means connected to said gauging means for generating a first signal indicative of said dimension at the traversing point of measurement, means interconnected with said traversing means for generating a second signal indicative of the instantaneous scanning location of said gauging means relative to said product, an operators station, recorder means located at said operators station and receiving said first and second signals for indicating the function thereof in two coordinates so as to graphically display said dimension profile, a plurality of means each interconnected with one of said local profile adjustments for generating a signal indicative of the position of said adjustment, a plurality of means located at said operators station and each receiving one of said position-indicative signals for registering the position of the corresponding local profile adjustment, means for actuating each of said local profile adjustments, and means at said operators station for manually controlling each of said actuating means independently.

References Cited in the file of this patent UNITED STATES PATENTS 2,370,163 Hare Feb. 27, 1945 2,511,853 Kaiser June 20, 1950 2,714,669 Wuppermann Aug. 2, 1955 2,750,986 Russell et al. June 19, 1956 2,788,896 Coleman Apr. 16, 1957 2,800,590 Gilman July 23, 1957 

